Alkylation fractionator

ABSTRACT

Alkylation-Fractionator having a settling section for separating liquid catalyst from the effluent of an alkylator. The lighter isoparaffins are stripped from the heavier fractions in a fractionation section below the acid settling section.

United States Patent 11 1 1111 3,713,615

Jones 1 1 Jan. 30, 1973 [54] ALKYLATlON-FRACTIONATOR [56] References Cited [75] lnventor: Edwin K. Jones, Kenilworth, 111. N D STATES PATENTS [73] Assignee: Universal Oil Products Company,

2,092,528 9/1937 Coubrough ..196/l39 X Des Flames, 1,831,887 11 1931 Sieck ..202 153 1,986,165 1/1935 Sieck ....202/l98 X [22] 1971 2,657,243 10/1953 Giraitiset 81. ..203/77 x [21] Appl. No.: 104,945 2,342,145 2/1944 lsham et a1. ..203/82 1,957,945 5/1934 Donnelly ..l96/l00 Related U.S. Application Data [63] Continuation-impart of Ser. No. 830,344, June 4, Primary Examiner-Norman Yudkoff 1969, Pat. No. 3,579,603. Assistant ExaminerDavid Edwards Att0rney-James R. Hoatson, Jr. and Ronald H. [52] 11.8. Cl. ..l96/l02, 202/154, 202/155, fl h 202/186, 202/176, 196/139 [51] Int. Cl ..B0ld 3/22, ClOg 7/00 57 ABSTRACT [58] Field of Search ..196/l00, 102, 139, 98;

' 202 1 155 153 19 17 154 172 1 Alkylation-Fractionator having a settling section for 203 39 74 g3; 23 2 3 233; 2 0 31 separating liquid catalyst from the effluent of an al- 353 359 343 kylator. The lighter isoparaffins are stripped from the heavier fractions in a fractionation section below the acid settling section.

6 Claims, 5 Drawing Figures Goa/ant 43 Q 42 P I 43 a C Vent Gas A/lry/afe 7'0 Storage PATENTEDJKHOIQB I 3.713.615

SHEET 10F 4 Figure Goo/ant 43 I I j cl enf Gas 35 52 Propane /'A llry/afion-Fmcfiona/or INVENTOR A/lry/afe To Storage Edwin K. Jones Kan $4444 A r romvsrs SHEET 2 OF 4 iiif IV l/E/V TOR: Edwin K. Jones A TTOR/VEYS ALKYLATION-FRACTIONATOR BACKGROUND OF THE INVENTION This application is a continuation-in-part of my copending application Ser. No. 830,334 filed June 4, 1969, now US. Pat. No. 3,579,603.

This invention relates to a catalytic alkylation apparatus. It specifically relates to an alkylation-fractionator which may be utilized with a processing system for producing high octane alkylated hydrocarbons.

It is well known in the prior art that catalytic alkylation utilizing sulfuric acid or hydrofluoric acid as the catalyst is an important chemical tool for preparing alkylated hydrocarbons and derivatives thereof. The commercial and industrial demand for these products is exemplified by the demand for isoparaffin hydrocarbons and alkyl-substituted benzenes of the gasoline boiling range and with the demand for alkyl-substituted aromatics suitable for conversion for surfactants, e.g., detergents, wetting agents, and the like.

The catalytic alkylation process to which the present novel apparatus is especially applicable consists of a process in which a mixture of hydrocarbons containing isoparaffins such as isobutane, isopentane, and the like, and olefins such as propylene, butylenes, isobutenes, amylenes, and the like, are mixed intimately in the presence of a strong acid catalyst such as hydrofluoric acid or sulfuric acid, for a time sufficient to complete the reaction. The effluent from the reaction zone contains isoparaffin hydrocarbons of higher molecular weight than the isoparaffins in the original mixture. Accordingly, for convenience, the term alkylate as used in the specification and claims is intended to embody the higher molecular weight reaction product from the alkylation reaction. Isobutane has been used almost exclusively as the starting isoparaffin because of its reactivity and availability to produce high quality alkylate products. In similar manner among the olefins, propylene and butenes have been used almost exclusively. The pentenes, and even higher boiling olefinic hydrocarbons, can be used according to their availability.

SUMMARY OF THE INVENTION Accordingly, it is an object of this invention to provide a novel alkylation-fractionator apparatus for use in a process for producing high octane alkylated hydrocarbons.

Therefore, the present invention provides an alkylation-fractionator apparatus comprising in combination: (a) a first vertically elongated housing section; (b) horizontal partition means disposed across said first housing section to form an acid settling section thereabove and a first fractionation section therebelow in the lower portion of the housing; (c) fluid inlet means into said fractionation apparatus for introducing a total fluid therein; (d) a second vertically elongated housing section; (e) horizontal partition means disposed across said second housing section to form a first liquid fraction withdrawal section and a second fractionation section therebelow and a second liquid fraction withdrawal section thereabove in the top portion of said second housing section; (f) liquid passageway means connected to the acid settling section and to the first fractionation section for passing liquid from the former to the latter; (g) means for supplying heat to the fluid of the first fractionation section; (h) liquid outlet means connected to the bottom end of the first fractionation section for removing liquid therefrom; (i) riser means connected to the first fractionation section and to the second fractionation section for passing the vapors from the former to the latter; (j) means supplying cooling to such vapors passing to the second fractionation section to condense a portion thereof; (k) passageway means communicating between the second fractionation section and second liquid withdrawal section for passing liquid and vapor between such sections; (1) means supplying cool ing for condensing vapors to the second liquid withdrawal section; (m) acid outlet means connected to said acid settling section for removing acid therefrom; and, (n) liquid outlet means connected to said liquid fraction withdrawal sections for removing the liquid fractions therefrom.

As will be described hereinafter in greater detail, my invention simplifies the design of an alkylation unit by using an acid settling section directly over a first fractionation section, thereby providing means whereby the acid utilized may be recycled and the hydrocarbon liquid gravitated to the first fractionation section. The fractionator may be utilized in conjunction with liquid acid alkylation catalysts, such as hydrogen fluoride and sulfuric acid.

My invention can be more clearly described and illustrated with reference to the attached drawings which are schematic representations of preferred embodiments of my invention.

DESCRIPTION OF THE DRAWING FIG. 1 is a schematical elevational view of one embodiment of the alkylation-fractionator apparatus of this invention. 1

FIG. 2a is an elevational view of a modified alkylation-fractionator of this invention.

FIG. 2b is the embodiment of FIG. 2a disposed in one housing.

FIG. 2c is a partial elevational view of the modified fractionator of FIGS. 2a and 2b.

FIG. 3 is a schematical illustration of the alkylation process utilizing the fractionator of FIG. 1 of the draw- Referring now more particularly to FIG. 1 of the drawing, there is shown an alkylation-fractionator apparatus 4 which comprises one vertically elongated housing 19. A horizontal partition means 25 is disposed across the housing to form an acid settling section 40 thereabove and a first fractionation section 41 therebelow in the lower portion of the housing 19. Fluid inlet means 3 is located in this intermediate portion of the housing and introduces a total reaction zone effluent into the alkylation-fractionator 4. The alkylation-fractionator apparatus 4 also includes a horizontal partition 31 positioned transversely across the housing 19 above the first partition means 25 to set off the section section of housing thereabove from the first section of housing. For larger capacities the section of the housing of FIG. 1 above acid settling section 40 can be separate and distinct. Above partition 31 a horizontal partition means 36 is disposed across the housing to form a first fluid fraction withdrawal section 32 and a second fractionation section 46 therebelow and a second liquid fraction withdrawal section 45 thereabove in the top portion of the housing. Section 45 will also serve as an acid settling section.

A conduit or weir 27 extends upwardly from partition means 25 to retain the fluid on the partition and to form a vertical fluid passageway means 28 connected to the acid settling section 40 and to the first fractionation section 41 for passing liquid to the fractionating section 41. A riser means 26 connects to the first fractionating section 41 and to the second fractionation section 46 for passing the vapors from the fractionating section 41 to the fractionating section 46.

The alkylation-fractionator 4 has means for supplying heat to the fluid in the first fractionation section 41 of the lower portion of the housing 19. In the drawing, the housing is shown with a lower reboiler 20 and a feed heater reboiler 21 that supplies heat in the first fractionation section 41 via a hot oil system represented by line 22 passing through reboilers 20 and 21. As shown in the drawing, exchanger reboilers 20 and 21 are located in wells 23 and 24 respectively. An outlet 11 is connected to the bottom end of the first fractionation section 41 for removing the liquid bottoms therefrom. An outlet 7 is provided to remove a side cut fraction from the first fractionating section 41.

Cooling is supplied to fluid above horizontal partition means 31 in the first fluid withdrawal zone 32 and the second fractionating zone 46 by condenser 34 and subcooler 33. Coolant via line 35 passes first through subcooler 33 which may contain baffles and the like and also through condenser 34. The subcooler 33 and condenser 34 cool the vapors which have passed from the first fractionating section 41 to the second fractionating section 46 to condense a portion thereof which may be removed via line 6. A conduit means 37 or other form of passageway means communicates between the second fractionating section 46 and the second liquid withdrawal section 45 in the top of the fractionator. Passageway 37 provides a means for passing liquid and vapor between sections 46 and 45. The cooling means 42 is used for supplying cooling for condensing vapors in the top portion of the housing. A coolant is supplied to the cooling means 42 via coolant line 43. A weir 38 is provided in conjunction with partition 36 to maintain the level of liquid on partition 36. The liquid is allowed to overflow the weir 38 and pass into the stripping section 39 where the hydrofluoric acid catalyst may be stripped from the liquid. When using sulfuric acid catalyst, stripping section 39 is not required. Heating means 51, supplied with steam via line 52, is provided in the stripper section 39 for supplying heat for stripping the hydrogen fluoride from the liquid flowing over weir 38. Outlet 8 is provided to remove the liquid from the stripping section. An acid outlet is provided to remove acid from acid settling section 45 to be recycled to the reactor. A first acid outlet 5 is provided in the settling section 40 to remove acid therefrom for recycling in the reactor. A vent gas outlet 9 is provided in the top portion of the column to release any gas not condensed by cooling means 42. Cooler 54 and line 55 are utilized in conjunction with the liquid being removed from line 11 at the bottom of the fractionator. I

The operation of the fractionation of FIG. 1 may be more clearly understood if the process flow diagram for an alkylation reaction and recovery process of FIG. 3 is referred to initially. in this process, there are three basic components, the reactor 2, the acid storage tank 12, and the fractionator 4 of P16. 1. The process shown in FIG. 3 is particularly applicable to the alkylation of isobutane with a butene-containing feedstock, although the process is also applicable to other isoparaffinic hydrocarbons and other olefin hydrocarbon feedstock to produce motor and aviation alkylates or higher boiling aliphatic alkylated compounds. Thus, the isoparaffin hydrocarbon to be alkylated may comprise isobutane, isopentane, one or more of the isohexanes,'mixtures of the aforementioned isoparaffins as well as the branched chain heptanes and other aliphatic hydrocarbons of branched type and chain structure. The process may also be utilized for the alkylation of aromatic hydrocarbons such as the benzene hydrocarbons, preferably benzene, to make detergent type products.

The olefinic hydrocarbon utilized as the alkylating agent in the process may comprise olefinic hydrocarbons such as propylene, 2-butene, l-butene, isobutylene, the isomeric amylenes, the hexenes, the heptenes and higher molecular weight olefinic hydrocarbons such as the C C, olefins for the production of detergent alkylates. The preferred olefinic hydrocarbons for use in the process have, however, from three to five carbon atoms per molecule.

Initially, the isoparaffin-olefin mixture is passed in line 1 into alkylation reaction zone 2. The isoparaffinolefin feed mixture is contacted with a liquid acid alkylation catalyst in alkylation reaction zone 2. The preferred liquid acid alkylation catalysts are sulfuric acid and hydrogen fluoride. The term hydrogen fluoride alkylation catalyst as used herein is intended to include catalyst wherein hydrogen fluoride is the essential active ingredient. Thus, it is within the scope of this term to use substantially anhydrous hydrogen fluoride containing various additives. Ordinarily, commercially available anhydrous hydrogen fluoride will be charged to the alkylation reaction zone as catalyst. It is, however, possible to use hydrogen fluoride containing as much as 2.5 percent water by weight.

The total reaction zone effluent, including the liquid acid alkylation catalyst, is continuously passed via line 3 directly into the alkylation-fractionator zone 4.

Settled acid catalyst is withdrawn via line 5 from an intermediate portion ofalkylation-fractionator zone 4 (hereinafter called zone 4) as an intermediate fraction and at least a portion of this fraction is passed from zone 4 via line 5 to alkylation reactor 2. if desired, a portion of this fraction may be passed to regenerator means (not shown) wherein the acid catalyst is regenerated in a regeneration zone.

lsoparaffinic hydrocarbon is withdrawn from zone 4 via line 6 from a second intermediate portion of zone 4 as a second intermediate fraction and this fraction is recycled to alkylation reaction zone 2 via lines 6 and 1.

Paraftinic hydrocarbon is withdrawn from a lower section of zone 4 as a side-cut fraction and is represented by line 7. Normally gaseous paraffinic hydrocarbons that have been condensed are withdrawn, preferably, from an upper portion of zone 4 via line 8 as a first upper fraction. Vent gas, if any, is removed from zone 4 via line 9.

Hydrofluoric acid catalyst may be withdrawn from a second acid settling section in the upper portion of zone 4 as a second upper fraction for recycle to the alkylation reaction zone or to the alkylation-fractionator zone. This stream is represented by line passing through orifice 10 (a), in FIG. 2. When utilizing sulfuric acid catalyst the second upper acid settling section is not required. High octane alkylated hydrocarbons from a bottoms portion of zone 4 are removed as product from the process via line 11. Fresh liquid acid catalyst may be added to the process from acid storage vessel 12 via lines 13 and 1.

Reference is again made to FIG. 1 for a more complete description of the operation of the fractionator 4. As will be understood by one skilled in the art, alkylation-fractionator 4 operates so that the section 40 formed between horizontal partition means 25 and 31 is an acid settling zone to take advantage of the fact that the hydrogen fluoride acid catalyst, for example, is heavier than the hydrocarbon mixture so that the catalyst gravitates downwardly to partition 25 as represented by numeral 29 for removal via line 5 from the alkylation-fractionator 4. The remaining hydrocarbon containing only dissolved acid catalyst overflows via passageway 28 and into well 24 where it is heated by feed heater reboiler 21. The remaining liquid overflows and enters a stripper or fractionation section 41 between feed heater reboiler 21 and lower reboiler 20. Normal butane vapors leave the alkylation-fractionator 4 via line 7 and alkylate is removed from the zone via lines 11 and 45. The vapor from the stripping section 41 or from feed heater reboiler 21 enters a rectification or second fractionation section 46 via conduit means 26 where part of the isobutane vapors are condensed by condenser 34. Uncondensed vapors are contacted by downcomingliquid in section 46 where additional isobutane is separated from the vapors. The major components of the remaining vapors of the present process are propane and the alkylation catalyst, hydrogen fluoride. The propane and hydrogen fluoride vapors pass through conduit means 37 and are condensed by exchanger 42. The condensed liquid flows into an hydrogen fluoride acid settling section 45 above partition 36 and the hydrogen fluoride is gravitated into the acid settling section as represented byline 48. Condensed liquid also flows down through passageway 37 to contact vapors passing upwardly. The propane is stripped of hydrogen fluoride in the reservoir-stripper 39, and is pressured to storage via line 8, while a portion of the propane may be gravitated back into the upper portion of the housing as reflux. The isobutane is separated as a liquid bottoms product above partition 31 from the propane rectification or fractionation section 46 and is gravitated into the isobutane receiving section 32 where it is passed to alkylation reactor 2 through subcooler 33 via lines 6 and 1.

Reference is now made to FIGS. 2a and 2b of the drawing where alternate embodiment of fractionator of this invention is shown with similar parts designated by the same numerals of FIG. 1 being primed. Of course the fractionator of FIGS. and 2b may be utilized with the process illustrated in FIG. 3. The embodiment of FIG. 2b differs from that of FIG. 2a only in that the two housing sections of FIG. 2a have been combined. In other words, the fractionator of FIG. 2a has two vertically elongated housings, sections 51 and 52, while the fractionator of FIG. 2b has one housing section 53. In both embodiments, a first horizontal partition means 25 is disposed across the housing sections to form an acid settling section 40' thereabove and a first fractionation section 41' therebelow in a lower portion of housing. The fluid inlet means 3' is disposed in the housing sections to carry the total fluid into the acid settling section 40'. The apparatus of FIG. 2b has a horizontal partition means 31' disposed across the housing section above the first horizontal partition means 25' to form a first liquid fraction withdrawal section 32' and a second fractionation section 46' thereabove in the upper intermediate portion of the housing 53. In the embodiment of FIG. 2a the first fraction withdrawal section 32 and second fractionation section 46' are located in the lower portion of the second housing section 52. An outlet conduit 6' is provided in first withdrawal sections 32' for removing the liquid fraction therefrom.

In both embodiments a horizontal partition means 36' is disposed across the housing sections above fractionation section 46' to form a second liquid fraction withdrawal section 45' thereabove in the top portion of the housing. Section 45' may also serve as an acid settling section when hydrogen fluoride is utilized. A vent outlet 9' is also provided in this portion of the housing. A liquid passageway means 28' is connected to acid settling section 40' and to the first fractionation section 41' for passing the liquid from settling section 40 to fractionation section 41'. A heat exchanger 50 is disposed in line 28' for supplying heat to fluid entering the fractionation section 41'The heat is provided by vapors passing from the fractionator portion 41 to the fractionator portion 46 via line or vapor riser 26'. A heat exchanger 20' supplied with hot oil through lines 22 is provided in the lower portion of the fractionation section 41' to supply heat in the fluid of the lower portion of the first fractionation section. It is noted that the heat exchanger or reboiler 20' is disposed in a well 23'. Liquid outlet means 11 is connected to the bottom end of the first fractionation section 41 for removing liquid therefrom. It is noted that no side-cut outlet is provided in the embodiment of FIGS. 2a and 2b. This outlet was eliminated to illustrate the fact that the bottoms product taken through line 11 may comprise more than the alkylated hydrocarbon and, in fact, may include a normal paraffinic hydrocarbon fraction to be separated from the alkylated hydrocarbon later. It is also noted that the heat exchanger 50 in FIGS. 20 and 2b establishes means for supplying cooling to the vapors passing from first fractionation section 41' to the second fractionation section 46' to cool the vapors passing to the fractionation section 46. A subcooler 33' is also provided in line 26' to condense additional vapors passing from the first fractionation section 41' to the second fractionation portion 46'. Passageway means 37 is provided in conjunction with horizontal partition 36' to provide communication between the second fractionation section 46' and the second acid settling section and second liquid withdrawal section 45' for passing liquid and vapor between such sections. Again as in the embodiment of FIG. 1 there is provided a cooling means 42 supplied by line 43 for supplying cooling for condensing the vapors in the top section of the housing. Again, outlets 10' and are provided in conjunction with the acid settling sections for removing the acid therefrom for possible recycle in a reactor. Liquid outlets 39 and 6' are provided in the liquid fraction withdrawal sections for removing the liquid fractions from the fractionator.

The operation of the fractionator of FIGS. 2a and 2b is similar to that of the one of FIG. 1 in that the total reaction zone effluent is introduced into the first acid settling zone 40' via inlet 3. For illustrative purposes, it is assumed that this effluent comprises the same components as was assumed for the operation of the embodiment of FIG. 1. The fact the hydrogen fluoride acid catalyst, for example, is heavier than the hydrocarbon mixture gravitates the catalyst downwardly to the partition 25' as designated by line 29' for removal via line 5' from the alkylation-fractionator. The remaining hydrocarbon above the acid level 29 containing only dissolved acid catalysts gravitates downwardly through line 28 through the heat exchanger 50 where it is heated and passed into fractionation section 41' of the lower portion of the fractionator. Fluid enters the fractionating section 41 where it is contacted with upcoming vapors. Any liquid remaining near the lower portion of the fractionator section enters the well 23 where it is reboiled. Any liquid overflowing the well 23 is removed via line 11' as product or for further separation. The vapor from the fractionation section 41 enters the second fractionation section 46' via the passage means 26'. In the passageway means 26' there is disposed the heat exchanger 50 wherein the vapor is cooled to some degree. Also disposed in the riser means 26 is a condenser 33 where further cooling takes place to condense more of the vapor to a liquid. The liquid condensate is basically isobutane vapors. It is noted that because of the location of condenser 33' and line 26' no pump is required to move liquids condensed to the second fractionation section 46. The uncondensed vapors comprising isobutane and propane as well as other hydrocarbons enter fractionation section 46' where more isobutane is separated fromthe mixture as a liquid. Some of the liquid isobutane in withdrawal zone 32' may have entrained propane therein which may be undesirable for recycling to the reactor. Such entrained propane may be stripped from the liquid as will be described hereinafter when reference is made to FIG. 20. When hydrogen fluoride is utilized as the alkylation catalyst, part of the hydrogen fluoride catalyst will also pass overhead with the propane through the riser means 37 The propane and hydrogen fluoride vapors are condensed by a water or refrigerant exchanger 42'. The condensed liquid flows into an acid settling section and liquid withdrawal section 45' where the hydrogen fluoride acid settles, as designated by line 48' and is removed via line and the propane is removed via line 39'. The propane may be saturated with the hydrogen fluoride catalyst and so a further step may be called for to strip the hydrogen fluoride catalysts from the propane in line 39. It is recalled that in the apparatus of FIG. 1 such a stripping means was included in the fractionator 4. It is also noted that passageway 37 serves as a means for introducing the liquid propane from the top of the housing to the fractionation section 46' for contacting the upcoming vapors.

Reference is now made to FIG. 20 where a propane stripper or reboiler has been disposed in the second fractionating portion 46' of the fractionator of FIGS. 2a and 2b. It is recalled that some propane remained in the isobutane liquid in withdrawal zone 32 of FIGS. 20 and 217. Thus, a well 60 having a liquid passageway 72 connecting to the withdrawal zone 32 is provided below the fractionating section 46' of the column. The well 60 is provided with a heater 61 which is used to strip the liquid in the well of entrained propane or other light fractions depending on the process utilized with. A longitudinal passageway 66 is provided in conjunction with the well 60 to establish a conduit for passage of the vapors to thereby bypass a portion of the fractionating section 46'. Thus, the alternative construction of FIG. 2a provides a means to eliminate much of the propane or other light fractions from the isobutane to be withdrawn through line 6' for recycle.

From the foregoing, it is apparent that the present invention provides for a novel alkylation-fractionator ap paratus which is more economical and efficient than previous prior art designs and which can be used effectively in a process for producing high octane alkylated hydrocarbons and alkyl-substituted aromatics.

I claim as my invention:

1. An alkylation acid catalyst fractionator apparatus disposed in a single vertical column comprising in combination:

a. a lower vertically elongated housing section;

b. horizontal partition means disposed across said lower housing section to form an acid settling section thereabove and a first fractionation section therebelow in the lower portion of the first housing section;

c. fluid inlet means into said acid settling section for introducing total alkylation reaction effluent thereto;

. an upper vertically elongated housing section;

e. horizontal partition means disposed across said upper housing section to form a first liquid fraction withdrawal section and a second fractionation section therebelow and a second liquid fraction withdrawal section thereabove in the top portion of said upper housing section;

f. internal liquid passageway means connected to the acid settling section and to the first fractionation section for passing liquid from the former to the latter;

means for supplying heat to the fluid in the first fractionation section;

h. liquid outlet means connected to the bottom end of the first fractionation section for removing liquid therefrom;

i. internal vapor passageway means extending through said acid settling section, connected to the first fractionation section and to the second fractionation section for passing the vapors from the former to the latter;

j. means supplying cooling to such vapors passing to the second fractionation section to condense a portion thereof;

internal passageway means communicating between the second fractionation section and the second liquid withdrawal section for passing liquid and vapor between such sections;

l. means supplying cooling for condensing vapors to the second liquid withdrawal section;

m. acid outlet means connected to the lower portion of said acid settling section for removing acid therefrom; and,

n. liquid outlet means connected to said liquid fraction withdrawal sections for removing the liquid fractions therefrom.

2. The alkylation-fractionator of claim 1 further characterized in that the horizontal partition means in said upper housing section forms an acid settling section thereabove and acid outlet means is provided for removing acid therefrom.

3. The alkylation acid catalyst fractionator of claim 1 further characterized in that said means for supplying heat in the first fractionation section comprises a preheater disposed in the upper portion of the first fractionation section and a reboiler disposed in the lower portion of the first fractionation section.

4. The alkylation acid catalyst fractionator of claim 1 further characterized in that the liquid passageway means and the vapor passageway means are disposed in indirect heat exchange relationship. 1

5. The alkylation acid catalyst fractionator of claim 1 further characterized in that there is provided a heating means to the upper housing section in communication with the second withdrawal section for stripping acid from the liquid therein.

6. The alkylation acid catalyst fractionator of claim 1 further characterized in that there is provided heating means to the second fractionation section for stripping lower boiling fractions from downcoming liquid. 

1. An alkylation acid catalyst fractionator apparatus disposed in a single vertical column comprising in combination: a. a lower vertically elongated housing section; b. horizontal partition means disposed across said lower housing section to form an acid settling section thereabove and a first fractionation section therebelow in the lower portion of the first housing section; c. fluid inlet means into said acid settling section for introducing total alkylation reaction effluent thereto; d. an upper vertically elongated housing section; e. horizontal partition means disposed across said upper housing section to form a first liquid fraction withdrawal section and a second fractionation section therebelow and a second liquid fraction withdrawal section thereabove in the top portion of said upper housing section; f. internal liquid passageway means connected to the acid settling section and to the first fractionation section for passing liquid from the former to the latter; g. means for supplying heat to the fluid in the first fractionation section; h. liquid outlet means connected to the bottom end of the first fractionation section for removing liquid therefrom; i. internal Vapor passageway means extending through said acid settling section, connected to the first fractionation section and to the second fractionation section for passing the vapors from the former to the latter; j. means supplying cooling to such vapors passing to the second fractionation section to condense a portion thereof; k. internal passageway means communicating between the second fractionation section and the second liquid withdrawal section for passing liquid and vapor between such sections; l. means supplying cooling for condensing vapors to the second liquid withdrawal section; m. acid outlet means connected to the lower portion of said acid settling section for removing acid therefrom; and, n. liquid outlet means connected to said liquid fraction withdrawal sections for removing the liquid fractions therefrom.
 2. The alkylation-fractionator of claim 1 further characterized in that the horizontal partition means in said upper housing section forms an acid settling section thereabove and acid outlet means is provided for removing acid therefrom.
 3. The alkylation acid catalyst fractionator of claim 1 further characterized in that said means for supplying heat in the first fractionation section comprises a preheater disposed in the upper portion of the first fractionation section and a reboiler disposed in the lower portion of the first fractionation section.
 4. The alkylation acid catalyst fractionator of claim 1 further characterized in that the liquid passageway means and the vapor passageway means are disposed in indirect heat exchange relationship.
 5. The alkylation acid catalyst fractionator of claim 1 further characterized in that there is provided a heating means to the upper housing section in communication with the second withdrawal section for stripping acid from the liquid therein. 